Pneumatic governors for compression-ignition engines and like applications



May 7, 1957 c, REDON 2,791,208

PNEUMATIC GOVERNORS FOR COMPRESSION-IGNITION ENGINES AND LIKE APPLICATIONS Filed May 2, 1955 2 Sheets-Sheet 1 REDON PNEUMATIC GOVERNORS FOR COMPRESSION-IGNITION May 7, 1957 c.

ENGINES AND LIKE APPLICATIONS Filed May 2, 1955 2 S heetsSheet 2 PNEUMATIC GOVERNORS FOR COMPRES- SIGN-IGNITION ENGINES AND LIKE AP- PLICATIONS Celestin Redon, Vincennes, France, assignor to Etablissements Berry, Lille, France, a corporation of France Application May 2, 1955, Serial No. 505,492

2 Claims. (Cl. 123-140) The present invention relates to pneumatic governors for compression-ignition engines and like applications, of the type in which a valve associated with the conduit which couples the induction system to the governor is controlled from the engine and maintains open the said conduit only during the suction periods. Such a pneumatic governor is disclosed in French Patent 1,053,322 which corresponds to U. S. Patent 2,642,855.

The known governors of this type are not in general very satisfactory in operation.

The present invention has for its object to provide a governor for diesel engines and similar applications, of the type referred to, which does not have these drawbacks.

A governor in accordance with the invention is characterised in that the valve always closes the conduit except for at least one instantaneous angular position of the crankshaft which corresponds to the maximum speed of each piston during the suction stroke. Instead of being open during the whole suction period, the conduit thus applies to the governor only a succession of transitory stages of depression which correspond with the greatest possible sensitivity to the variation of the engine speed alone, without taking account of the fluctuations of the delivery of air during one whole period.

A governor in accordance with the invention, in which the distribution member comprises a slide-valve actuated by a shaft driven from the engine is further characterised in that the surface of the said slide-valve is closely applied against one single fixed surface into which the two branches of the conduit lead.

By means of this arrangement, complete fluid-tightness is obtained. In accordance with a further feature, the distribution member or valve is provided with a rotating plate which is rigidly mounted for rotation with, but free to slide laterally along the cam-shaft of the injection pump, and which is urged towards a fixed plane surface into which lead the orifices of the conduit, by means of springs which derive their support from a flange fixed to the said shaft.

One form of embodiment of the invention is described below, by way of example, reference being made to the attached drawings, in which:

Fig. 1 is a view in side elevation, with portions in diametral cross-section, of a pump-governor assembly in accordance with the invention;

Fig. 2 is a corresponding view in front elevation, with parts in cross-section following the broken line II-II of Fig. 1;

Fig. 3 is a view to a larger scale of the valve in crosssection, following the line III-III of Fig. 2.

Fig. 4 is a view of the valve plate in elevation following the arrows 1VIV of Fig. 3.

Fig. 5 is a view of the greasing nipple and of the mounting arrangement of the valve in cross-section following the line V-V of Fig. 2.

Fig. 6 is a diagrammatic view of the general installa- Z,7 9Il,Z08 Patented May 7, 1957 ice tion of the part of the engine which includes the pumpgovernor assembly.

In the form of embodiment shown, which relates by way of example to an application of the invention to a four-stroke diesel engine with two cylinders with cranks at there is shown at 10 in Fig. 6 the induction system of the engine, and at 11 the butterfly-valve mounted in the pipe 10 so as to regulate the air intake. A conduit 12 is connected to the induction system in the vicinity of the butterfly-valve 11 and extends (see Figs. 1, 2 and 3) to a port 14 formed in the fixed plate 15 of a valve 16. The valve 16 (see Figs. 1 to 6) is placed at the end of the injection pump 17 of the diesel engine, and is co-axial with the cam-shaft 18 of the said pump. There are shown at 19 the two delivery fuel pipes which are respectively coupled to the injectors of the two cylinders of the engine (not shown). At 20, there is shown a depression regulator and at 21, the air conduit which is coupled to the regulator 20. The governor 20, fixed to the frame of the pump 17, is arranged in accordance with the invention so as to allow a quantity of fuel to pass into the pipes 19 which is a function of the depression in the conduit 21, the fiow of fuel being lower as the depression increases and viceversa. Any suitable kind of device, with bellows, diaphragm or other arrangement (not shown) may be provided on the governor for that purpose.

The conduit 21 which controls the governor 20, extends as far as a port 22 formed in the fixed plate 15 in the vicinity of the port 14. The ports 14 and 22 are arranged in line (see Fig. 2) along a circumference co-axial with the shaft 18 and open out into an external radial plane face 23 of the plate 15 (see Figs. 3 and 5). The latter is fixed to the casing of the pump 17 by'means of two diametrically-opposite screws 24 (Figs. 2 and 5), and is of annular form so as to extend in a spaced manner around a conical extension 25, having a threaded end portion 26, of the shaft 18 (see Fig. 3).

On the conical extension 25 is tightly driven the internal conical portion 27 of the bore of a sleeve 28, the external part of the bore being cylindrical at 29. The sleeve is provided with an external flange 30.

A nut 31 having a projecting head 32 and an external cylindrical surface 33 is engaged in the portion 29 of the bore of the sleeve, and is screwed on to the threaded end portion 26. During this screwing-up operation, the projecting head 32 pushes against the sleeve 28 so as to fix the latter solidly on the shaft 18 by the friction of the conical portion at 25.

The flange 30 of the sleeve 28 is provided with four drilled holes 34 (see Figs. 1 and 4) parallel to the shaft 18 and spaced apart at regular intervals along the periphery. Two small pillars 35 (Fig. 1) are engaged in two diametrically-opposite holes 34, whilst two springs 36 acting by compression are engaged in the two other holes 34. The small studs or pillars 35 and the springs 36 are engaged in four corresponding holes 37 formed in a movable plate 38 of the distributor valve 16 (see Figs. 1, 3 and 4). The plate 38 is of annular shape and is mounted around the sleeve 28; it is driven in rotation from the shaft 18 through the medium of the sleeve 28 and the studs 35, and is constantly forced by the springs 36 against the face 23 of the fixed plate 15.

Cavities 39, the number of which is equal to that of the cylinders of the engine, that is to say two in the form of embodiment shown, are formed in the face of the moving plate 38 adjacent to the face 23 of the fixed plate 15. Each cavity 39 is of elongated arcuate form (see Fig. 4) so as to be able to extend opposite the two ports 14 and 22 of the fixed plate and thus to place the two conduits 12 and 21 in communication when the shaft 18 takes up a pre-determined angular position.

The distributor or valve 16 thus formed by the fixed plate 15 and the moving plate 38, is enclosed in a casing 40 which is fixed to the casing of the pump 17 by means of screws 41 passing through the fixed plate 15 (see Figs. 2 and 3). There is shown at 42 (Figs. 2 and a greasing nipple associated with the valve 16.

During operation, the shaft 18 of the injection pump rotates at half the speed of the crank-shaft. The moving plate 38 is locked on the shaft 18, and the cavities 39 are so arranged that one of the cavities connects together the two ports 14 and 22 when the piston of one of the cylinders is at its maximum speed during the suction period, whilst the other cavity 39 couples together the two ports 14 and 22 when the piston of the other cylinder is at its maximum speed during the suction period. At all other times, these two ports remain isolated.

In these conditions, the pipe is only coupled to the governor when one of the pistons is at its maximum speed during the suction period, that is to say when the induction system 10 has a maximum and well-defined depression during the instantaneous cycles considered of the two cylinders. It is this constant depression which controls the flow of fuel in a well-defined manner, until one of the cavities 39 again connects the ports 14 and 22, the depression being then able to assume a different but always quite definite value, which ensures stable control without erratic operation.

It will of course be understood that the invention is not limited to the form of embodiment described and shown, but embraces all alternative forms of its various members and in its applications. The invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims.

What I claim is:

1. In a pneumatic governor for compression-ignition engines, having a conduit coupling said governor and the induction system of the engine, and a valve maintaining 4 open said conduit only during the suction periods, means in combination with said valve for keeping said conduit closed except for at least one instantaneous angular position of the crank shaft of the engine corresponding to the maximum speed of each piston during the suction period, said means comprising a plate fixed on the injection pump of the engine and coaxial with the cam shaft of the pump, two' orifices in said plate arranged in a curved line along a circumference coaxial with the shaft of the pump, two conduit branches connected to said orifices respectively, a valve plate rotating in unison with the shaft of the pump and having an annular cavity along a circumference coaxial with the shaft facing the orifices of the fixed plate and of a length to connect said orifices in one angular position of the crank shaft, means for resiliently pressing said valve plate against the first mentioned plate, said shaft having a conical extension, a sleeve fitting within bores of the two plates and provided with an internal conical surface tightly fitting the conical extension of the shaft, an external flange on said sleeve, and a nut threaded on the end portion of the shaft for forcing the sleeve solidly on the shaft by the friction of the conical surfaces of the shaft and sleeve.

2. A device as set forth in claim 1, wherein the flange of the sleeve is provided with four holes parallel to the shaft spaced apart at regular intervals along the periphery of the flange, said movable plate of the distributor valve having four corresponding holes, two studs traversing two holes of the flange and corresponding two holes of the movable plate, and two springs fitting the other two holes of the flange and the other two holes of the movable plate, so that the movable plate is rotated with the shaft through the medium of the sleeve and the studs, while the springs force the movable plate against the fixed plate.

References Cited in the file of this patent UNITED STATES PATENTS Vanni June 23, 1953 

